This invention relates to a thermal-printer operated by the thermal printing principle, using a thermal-head which is now extensively used in various information devices in order to record the information.
The types of thermal-printer are divided into a line type thermal printer incorporating a line type thermal-head in which a number of minute heating elements are disposed in a line along the width direction of recording paper, and a serial type thermal printer in which a thermal-head with a limited number of heating elements travels repeatedly along the width direction of paper.
Since the line type thermal-head is equipped with a number of heating elements disposed in a line, the driving of these individual heating elements requires not only highly complicated controls of those, but controls of feed motor and the transfer of head driving data.
As a control device of such, a general-purpose control board having a function of either the parallel or serial control function, or such has been used.
However, in accordance with the expanding and diversifying printer market in these days, the printer functions had to be diversified also according to the purposes. For instance, the computer terminal printer should have high-speed and high-quality printing functions in addition to the lighter load to the driving circuit.
On the other hand, the printer for portable equipment has to be of low cost and compact design, and these can not be satisfied by a general-purpose control board, and the printer controller satisfying these requirements has to be developed.